By Ryan Tumilty, CBC News Ottawa, May 30, 2019
The Carillon dam is the Ottawa River's final drain.
Water from every one of the river's many tributaries and reservoirs — every drop from its vast watershed — eventually flows through the hydroelectric power station's gates, about 130 kilometres east of the capital.
On April 30, when the river reached this spring's peak, a record 9.2 million litres surged through the dam each second, enough to fill nearly four Olympic-size swimming pools. That's more water than cascades over Niagara Falls.
https://www.cbc.ca/news/canada/ottawa/ottawa-flood-different-2017-2019-1.5153617